I have 2 SM-AFR and 1 SM-V/B hooked into my car with the IMFD Adaptor plugged into my KIWI 2 Bluetooth. When I attempt to add the sensors to my paid Torque app through either the logging settings or dashboard, I only get see 1 AFR sensor and it stays at 0.69 Lambda, never moving. I tried just the AFR sensor by itself without being hooked up to anything else and it shows the same. It works in DashCommand app, but I hate using that app for logging.

Is there anything I’m doing wrong?

Full setup is:
SM-AFR 1 has the terminator jumper installed
SM-AFR 2 has its RX connected to the TX of SM-AFR 1, terminator removed
SM-V/B has RX connected to TX of SM-AFR 2, terminator removed
The IMFD Adaptor is hooked up to TX of SM-V/B.

Quote from Capp777 on July 17, 2014
How are you addressing the various sensors in
the pid editor?

Ian added support for these devices back in
version 1.8.32 according to the changelog…
but you are the first person to post about
actually using these devices (that I’ve seen).

When I go to the “manage extra PID/Sensors” menu it shows the following as the last item and is automatically added when I start the app:

ECU Custom PID
Wideband Air/Fuel
PID: 0ccd90
Unit: lambda
Max/Min: 0.0/0.0
Equation: null

It is non-editable, and when I add a PID with the same settings it says no response. The add display on the dashboard shows the plx sensor icon on the one it adds, but it just reads 0.68. I haven’t found the PID address DashCommand uses for the sensors, but it reads the data. I prefer using Torque though, I can customize the view better.

I don’t see any PID’s in the user manual, but the user manual is just a sheet of paper. Only thing it says under troubleshooting is:

“Is there only OBD II data showing?
Change the hardware settings in the app to ‘Kiwi’ 2 + iMFD”

I do see on the Kiwi SDK page that there is information about reading from the iMFD, but it is going into the application development code, not what the end user would see. It says you have to switch to iMFD mode, then read the stream.

It says the Address for the Widebands are 0, the Vacuum is 3, and the Boost is 4.

When I get home from work tonight I will see if I can figure out what the PID’s are for them, but I hate doing bit moving, gave me headaches programming radar systems in the USAF. Just don’t know if it will work since you are not requesting information from the ECU, you are reading a stream of data from the iMFD.

Thanks for the response, I didn’t work on the PID anymore, I took my surface and used C# to read the data directly from the iMFD through bluetooth. I have 2x 3rd Gen Widebands and a Vacuum/Boost sensor, this is the data that was coming in:

Sensor 0, Location 0: 255 (Wideband 0, AFR 20.04)
Sensor 18, Location 0: 573 (Battery Voltage I believe)
Sensor 25, Location 0: 0 (I think response time)
Sensor 26, Location 0: 1000 (Sensor health?)
Sensor 0, Location 1: 255 (Wideband 1, AFR 20.04)
Sensor 18, Location 1: 573
Sensor 25, Location 1: 0
Sensor 26, Location 1: 1000
Sensor 3, Location 0: (Vacuum 0)
Sensor 4, Location 0: (Boost 0)

I did the shifting bits to convert the MSB and LSB into a integer to get the sensor type and value. The location byte was straight integer conversion. I cheated though and used the SDK they have to convert the data value to the value I wanted.

It returns a number between 0-255, you just use the formula to convert it to what you want.

Quote from Capp777 on July 21, 2014
How would that work with temperature
sensors with °F and °C units choices?

Wouldn’t that number produce two different
results? Which would be correct?

Does the complete frame of data include data
values for each units choice (for every sensor)?

It will be the same value, just a different formula that you have to use to convert it. The sensor will see the same thing which is just a voltage or resistance, it has no clue what units you are reading. In the software Ian is writing he converts it based on what unit you want.

If the serial data is coming through with 100 for Air temperature, you would use the following formulas:
Celsius = 100
Fahrenheit = (100/.555 + 32)

For a Wideband with the byte data of 130:
Lambda = (130/3.75 + 68) / 100 = 1.026
Gasoline AFR = (130/2.55+100)/ 10 = 15.098

If you see the SDK document that says ‘if(units == 0)’ parts, the ‘units’ variable is coming from the programmer himself, PLX is only providing the ‘data’ and ‘sensor’ variable.

Hope this explains it because I am a terrible teacher.

That is if you are reading the analog output like you are plugging it into a SCT tuner.

There is another SDK document that is on their website, I will try to find the link. It is a lot better.

http://www.plxdevices.com/AppNotes/PLXApp018.pdf

Quote from Capp777 on July 21, 2014
Thanks for the link… that document is different
than the code page I found under support.

Now I’m curious why they are representing a
255 max raw value with 12 bits…

Thanks again!

Voltage = Data / 51 would work with above.

The 0-255 data is for AFR’s, I’ve seen 573 and 1000 also, so they are using 12 bits when it is necessary.

The 573 was off sensor 18 which is voltage, 1000 was sensor 26 which I think is health.

I was wondering if the OBDII command
push button display’s test command feature
could be used to see the raw response and return
it back to OBD mode.

There is a pushbutton display for executing
OBDII commands which has a way to test
the response when you create the display.

The command string is similar to the custom
init string format… multiple commands are
separated by \n (not sure if \r would work
though).

Does the following sequence seem correct?

Switch to iMFD mode and
trigger > prompt.

>– \r

iMFD data frame returned
once it is complete. (52 bytes?
in your case).

Switch back to OBDII mode and
trigger > prompt.

>+ \r

Ready for next command.

>

http://torque-bhp.com/wiki/Custom_Init